sasd97, In Windows 8, visual state stupidly switched in code, in the SizeChanged handler. In Windows 8.1, the standard templates use a LayoutAwarePage, which itself switches the data, however, it only determines if the application has been snapped (xs how to translate, in short, takes only half of the screen).
In your case, as far as I know there is only one option - to catch SizeChanged and change the steyta manually.
If you are writing under Windows 10, use AdaptiveTrigger.